This invention relates to a blanking operation, and in particular, to a presser assembly for supporting carton blanking scrap during a blanking operation.
In the manufacture of cartons, small sheets of material are cut out of larger sheets. These smaller sheets are known as carton blanks which, in turn, are formed into boxes. The blanks are formed during a process known as a blanking operation.
In a blanking operation, the blanks are cut, but not removed, from the large sheet of material. After the blanks have been cut, the sheet is positioned over a frame for support. The frame includes large openings which correspond in size and in position to the carton blanks previously cut. Below the frame is a mechanism for stacking the blanks.
In order to knock the carton blanks from the sheet of material and hold the scrap material, a presser assembly is used. The presser assembly includes a support tool having a presser member and a presser rail depending therefrom. The presser rail is biased away from the support tool. As the support tool is lowered, the presser rail engages the sheet of material such that the large sheet of material is secured between the presser rail and the frame. The support tool continues to be lowered such that the presser member engages the carton blanks and knocks the blank out of the sheet of material. The carton blanks fall onto a stacking mechanism wherein the blanks are stacked.
If a carton blank is not completely knocked out from the sheet of material, it is possible that the carton blank scrap may be forced by the presser member onto the stacking mechanism. In addition, if the presser rail does not adequately hold the carton blanking scrap, the scrap may fall onto the stacking mechanism. A carton blanking scrap in the stacking mechanism may jam the mechanism thereby causing downtime, and hence, expense.
In order to securely hold the carton blank scrap, the present day presser rails are interconnected to the support tool by a plurality of guide cylinders. Each guide cylinder biases the presser rail away from the support tool. This gives the presser rail a certain amount of flexibility when engaging the carton blanking scrap. However, even with this limited flexibility, present day presser rails have been found to be inadequate.
Therefore, it is the primary object and feature of this invention to provide a presser assembly having a presser rail which securely holds carton blanking scrap during a blanking operation.
It is a further object and feature of the present invention to provide a presser assembly having a presser rail which is durable and maintains its shape over an extended period of time.
It is still a further object and feature of the present invention to provide a presser assembly which is easy to assemble and easy to mount to standard blanking operation machinery.